Abstract
PURPOSE: To investigate clustering patterns of 10-2 visual field (VF) defects in normal-tension glaucoma (NTG) patients with central VF involvement and identify specific clusters associated with visual acuity (VA) loss across disease stages. METHODS: NTG patients who underwent 24-2 and 10-2 VF testing, optical coherence tomography (OCT), and OCT angiography were included. Based on 24-2 VF mean deviation (MD), eyes were classified as early-stage (MD ≥ -6 dB) or moderate-to-advanced (MD < -6 dB). Hierarchical cluster analysis (HCA) was applied to 10-2 VF total deviation (TD) values to identify spatial patterns of central VF defects (CVFDs). Pearson correlation and regression analyses assessed relationships between cluster mean TD (mTD) and VA, and determined predictors of VA loss. RESULTS: A total of 167 eyes (68 early-stage, 99 moderate-to-advanced) were analyzed. HCA identified four clusters in entire cohort and early-stage group, and six in the moderate-to-advanced group. Cluster 3, located in the inferotemporal region, showed the strongest correlation with VA (r = -0.474 in early-stage; r = -0.762 in moderate-to-advanced; all P < 0.001). Regression analysis confirmed that Cluster 3 mTD was significantly associated with VA in both stages. In moderate-to-advanced eyes, Cluster 3 mTD and macular ganglion cell-inner plexiform layer thickness significantly predicted VA worse than 20/25 (OR = 0.759, P = 0.004; OR = 0.915, P = 0.01). CONCLUSIONS: HCA demonstrated consistent spatial patterns of CVFDs across various stages of NTG. The inferotemporal region (Cluster 3) consistently correlates with VA and serves as a key marker of VA loss.